Fusible link.



0. H. IMAN.

.FUSIBLE LINK. APPLICATION FILED MAR.1C 1914.

1,120,817. Patented n -1'5. 1914 prurnn srarss PATENT ore-ion OKLA H. IMAN, OF CHICAGO, ILLIl-IOIS, ASSIGNOR TO VCIGTMANH 6: COMPANY, OF

CHICAGO, ILLINOIS, A CORPORATION OE-ILLINQES.

niaasrz'.

Specification of Letters Patent.

, FUSIIBLE LINK.

Patented Dec. 15, 1914:.

Application filed March 16, 1914.. Serial No. 824,841.

fusible links. and refers more particularly tofusible links used for effecting the automatic closing of doors-r windows in case of fire, when the temperature of the link reaches a certain predetermined amount.

The salient objects of the present invention are to provide a fusible link which will positive. and certain in operation under all the conditions met with in practice; to provide a'fusible link which in itself is furnished with means to positively insure its opening when the solder has fused, whether the link be subjected to tension or not; to

provide a link which will be capable of -sus-- taining a large amount of tensile load with- .out danger .of coming apart under normal conditions; to pro ide a link which will be proof against the clogg ng efi'ects of calmmine, paint, grease, dust, or other dirt; to

provide a fusible link which will be simple construction and economical ofmanufac- MP3, and in general an improved fusible k. of the character referred to.

i. v invention consistsin the matters hereinafter pointed out and described in con-' nection with the accompanying drawings, in which- 7 Figure 1 is a plan view of my improved fusible link with a 'shortlength of chain attached to each end; Fig. 2 is an elevation of Fig. 1; Fig. 3 is a longitudinal sectionv through the link proper; Fig. 4; is a section taken along the line,4. l of Fig. 1; Fig. 5 is a view showing the various parts of the link in partially assembled position, prior to soldering and Fig. shows the three elements of the link in separated position.

Referring to the dra vin s, it will be seen that the liiik consists of three parts,the two main separable elements 1 and 2, and the spring The two main members 1 and both alike and are formed .by means of suitable dies, preferably of phosphor bronze or other similar metal which will not corrode and yet will have considerable mechanical strength. Each of these mam members is substantially flat in general outline,

but has a flange formed up and extending almost completely around its periphery for the purpose of giving additional mechanical strength. Eachpart of the link has a large hole in the circular end portion for the reception of the chain at in which the link is interposed. These holes are reinforced with eyelets or gromets 5 in order to prevent the end links of the chain from tearingthe relatively thin metal of the link.

As will be seen from an inspection of the drawings, the tail of each of the two halves of the link is punched at two places along thecent er line of the link to form a pair of cone-shaped projections 6 adapted to internest with the cones of the companion member of the link. One of these cone-shaped proturbances is punched out of the metal and projects on one side of the link, whereas I the other is formed on the reverse side; this being for a purpose which will hereinafter appear. Between the two members 1 and 2 of the link I place the spring 3,- which is provided with a pair of holes-7 located the same distance apart as the cone-shaped projections in the tails of the two main parts of the link. I The size ofthe spring is substantially equal to the amount of overlap of the two main members of the link, and,

as shown in Fig. 5, its normal shape is curved so as to force the parts of the link apart whenit .is inserted between them. It will be seen by an inspection of Figs. 3 and 5 that one ofthe projections in one half of 3 the link passes through one of the holes in the spring, and the corresponding coneshaped projectiononthe other half of the link passes throughthe other hole. in the 'SpIlIW.

In manufacturing the link,- I assemble the two main members of the link in inter-nested relation, withthe spring between them, and press the assembly tightly together-with a pair of pliers provided withopposed points .which thus cover up a very small amount of the. exposed surface of the link. Having dipped the link in a suitable flux, I immerse itv in a bath of'readily fusible solder which thus flows into the crevices of the link. The

solder .is set plunging the link into cold water, and it is then ready for the-loading with additional solder. This extra .loalding of solderv can be seen; at 8,9, -l0-'and '11 .111

' of construction shown or described, exceptcome apart. vThere are a number, of reasons for applying this additional load of solder to the edges of the joints of the .link. In

the first'place, it strengthens the link-materially at a point where it is weakest'to ,re--

slst bendmg strains; secondly, it prevents corrosion of the 1o1nts oftthe'nnk, and,

thirdly,'it prevents any possible chance for the link to become sluggish inaction by the clogging of the oints with calc mme, paint,

or other dirt.

So farfasl am aware, my improved'link is the first one .to be provided with aselitcontained release spring in the separable joint of the link, and by employingthis self-- contained spring-I obtain several ,advana tages in protection and operation, which are" as follows:-First, the instant that the solderof the'link melts, the spring at' once'; forces. thetwo members apart, in spite-0 i any clogging effect due to the presence ofpaint or calcimine," and regardless "of whether there is a small or a large amount of tension on the chain to which the link is attached. In the second place, the'springl itself imparts additional strength'tothe'sole' dered joint since the-holes in the spring en- T gage the cone-shaped protuberancesiof opposlte halves 'ofthe link. ,Thirdl'y,--itpro-' vides the proper spacing-.betweenthe two main members of the links to allow the coneshaped protuberance's to internest w th-each;

other properly.- T'he-cone-shaped protuber v ances I have found increase the strength-jot the link very materially. In fact my im- .proved link is capable of-sustaining'several times the load of anordinary fiat linkhav- -ing the same overlapping area but Without the internesting cones, By providing a pair ofthe cones,"jI am enabled to assemble the parts of the link together'so that-they" will always be in perfect registerand-properalinement. This makes all of the links 'e'x-- actly alike and "interchangeable. l

I do not wish to'be, limited to the details as. specified inithe appended claims.

I claim 1.. A fus'ble link, comprising-two thin sheet-like ymembers assembled overlapping relation, a plate springinterposed be tween sa d two members and normally tending to force said members apart, and readily. fusible solder surrounding said sprmgand maintaining thetwo members of-the link 'j substantially parallel separable members 2. A fusible link, comprising two. thin sheet-like-I'nembers stamped .into similar are.

in assembled relation;

lief configuration and nested togetherin .65. nlapping relationand readily fusible slder, and a plate-springlinterposed 'betg een said two members 'andinormally ten mg to force them apart.

3. A 'fusible link, comprising a pair of.

hin sheet-like members each provided with a projection and a recess, the two being as seinbledin internestedand overlapping relation, the'projection on ea'ch 'ot the members enteringthe recess in the other member,

and apiece of sheet metal interposed be-' tween the 'two members and provided with a pair of apertures engaging the projections 0 the two overlapping members, and readil g insiblesolder uniting the surfaces of the interposed sheet and the overlapping surfaces 'of the'two main members. I

'. 14. A'iusible link, comprising-a pair of similar thin sheet metal members each pro-. vided with a beveled, projection and a beveled recess and assembled in overlapping and ,internested relation, the beveled projection I of eachmemberj entering the beveled recess a pair jdf apertures each engaging a projecof the other'member, a spring-plate inter- ;po's' edbetween said members normally tending to fforce 1themapart' and provided with go I tiong'on" one; of. the rm'ain members, and..

readily I fusibleJsolderfuniting the surfaces "of the spr ng and the overlapping surfaces. 'ofthe-two 'm'ain' members..f v

A ffusibleialink, comprising a pair at similar thi1r sheetilike members each provided fwith lation, the comet each member entering the recess, of the other member, a plate-spring interposed-between the: two members and provided witha pair-of apertures each registeringlwith andeng'aginga cone on one of the links, and readilyfusible solder uniting theoverlapping f. surfaces of the two main members.

6. A' fusible link, comprising a pair of conekshaped projection and with. a; cone-shaped recession the same side off-the'n1err1b'er, the-two members being assembled internested and overlapping reseparable members having a pair of overlapj ping surfaces united by readily fusible sol-v der', and provided with resilient means tending' to force said members apart and acting in a direction at an-angleto saidsurfac'e's.

Z. A fusible link, comprising a pair of separable members having a pair of overlapping surfaces united by readily fusible solder and adapted to transmit tension in a di rection substantially parallel with said overlapping surfaces, and provided with resilient means tending to force said members ap rt and acting in a direction at an angle to the-direction of sai'dtension.

8. A fusible lmk, comprlsmg a pair of having a pair of overlapping surfaces united by re'adily fusible solder ,and adapted to members, anda spring tending to force said interposed between said oi erla-pping surmembers apart and actmg in a dlrectlon at faces and acting in a direction at an angle an angle to said surfaces. to said surfaces.

, 9. A' fusible link, comprising a pair of ORLA H. IMAN. v 5 thin sheet-like members having a pair of Witnesses:

overlapping substantially parallel surfaces SADIE M. RYAN, united by readily fusible solder, and a spring C. A. SOANS. 

